I know that a one-time pad requires a non-repeating key at least equal to the length of the message to encode, but I have no idea how (or if it is even possible) to decode such a message using a one time pad. Does anyone have any ideas?

  • This is off-topic. With a OTP you typically decrypt the ciphertext with the same key and reverse the method that you used to encrypt the plaintext - see the Wikipedia article Oct 1 '12 at 23:57
  • You need to know how the one-time pad was convolved with the input source. It may have been a simple bit-wise XOR, in which case you just XOR again. Or it may have been something a bit more complex. Oct 2 '12 at 0:46
  • You have get more luck asking security.stackexchange.com
    – Dave
    Oct 2 '12 at 8:07

Do it the same way it was encrypted, but backwards.

  • With the most common kind of one-time-pad, you use xor to combine keystream and text which is even identical in both directions. Oct 26 '12 at 12:27

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